This study investigates the effect of cellulase enzyme on enhancing the pectin extraction efficiency from Mesona chinensis Benth, commonly known as black grass jelly from Lạng Sơn province, which is a rich but underutilized source of pectin. The raw material used was dried black grass jelly (including both stems and leaves) with a moisture content of 14.37% and an initial pectin content of 29.18%. Extraction parameters investigated included cellulase enzyme concentration (0.5%, 0.75%, 1%), processing temperature (120°C, 180°C, 210°C), and processing time (120, 180, 210 minutes). Results showed that enzymatic treatment significantly improved pectin extraction yield compared to the non-enzymatic method. Optimal extraction conditions were determined as 0.75% cellulase enzyme concentration, 55°C processing temperature, and 180 minutes of extraction time. This study provides a scientific basis for the application of cellulase enzymes in pectin extraction from Mesona chinensis, contributing to the optimization of production processes and increasing the industrial value of this plant in the food and pharmaceutical sectors.